1. Field of Invention
This invention relates to rear suspension bicycle frames, particularly off-road rear suspension bicycles used on terrain with varying conditions and surfaces, with loose and immovable objects to travel over.
2. Prior Art
Rear suspension has proven to be a benefit in comfort and performance bicycles. This benefit is especially realized with off-road bicycles. Rear bicycle suspension absorbs shock from road and/or trail surface variations. By absorbing impacts, tire traction is improved giving the rider improved control of the bicycle. Improved tire traction is a benefit in lateral, forward, and rearward directions. Cornering, turning, accelerating, climbing, and braking are improved.
Typical rear bicycle suspension designs found in prior art are comprised of linkages, similar to those used in automobiles and motorcycles. The composition of rear suspension linkages make up the suspension chassis. Prior art designs have attempted to increase pedaling efficiency through arrangement of the linkages while still providing shock absorption for improved traction in turning and braking. Four-bar linkages and similar single swingarm linkages have commonly been used in prior art linkage arrangements for rear suspension. Prior art and bicycles of these types in general have always had an undesirable high center of gravity. Overcoming taller trail obstacles has also presented challenges to even the most skilled riders.
More recently, the inventor of the present application has developed a unique design that improves pedaling efficiency and handling over prior art designs, while allowing for maximum bump absorption for many different types of terrain. Even though designs such as U.S. Pat. Nos. 5,957,473 and 5,509,679 have advantages over prior art designs, limitations exist on their geometry, inherent high center of gravity, overcoming immovable trail objects, and other performance characteristics. These designs are well known in the field.
More recent designs in the field such as U.S. Pat. Nos. 6,450,521 and 6,203,042 have addressed other issues with certain general performance characteristics, but still fail to recognize inherent high center of gravity issues, overcoming taller immovable trail objects, and performance characteristics related to a high center of gravity.
As a result, there has been a need for an alternative design that provides superior performance over prior art of the present application. There has been a need for a design with the superior handling of a low center of gravity bicycle that responds when traveling over larger trail obstacles.